I'd say it's not. Usually when flowers are cut, they die. After something is dead, it's not living anymore is it? It's debatable though.
Yes, if you 'dead-head' or cut off the heads of sunflowers, the plant will usually continue to produce more flowers. This varies somewhat with the variety of sunflower and the bushy type will produce the most flowers when flower heads are removed.
flowers... that have been cut...
Yes, it will help extend the flowering season of the plants.
It is better to deadhead all annuals as when they set seed they stop flowering.
cut.
cut flowers. fleurs coupées
It is believed that adding sugar to the water for cut flowers provides the flowers with a food source since the flowers have been literally "cut off" from their food supply.
White Flowers for the Dead was created in 1978.
The duration of White Flowers for the Dead is 1.5 hours.
it kills bacteria in the water prolonging the life of cut flowers
Cut flowers will live for quite some time if you care for them properly.